I am not 100% sure about the status of a TCP/IP stack on the 7250 is -- but I think it will have one, since it is rumored to have EV-DO and have the ability to be used as an external modem for a laptop.

The best thing to do is wait until the 7250 has been reviewed by somebody. Initial release of Blackberries can be slightly buggy (just like when the first time Treo 600 was released), until a couple of firmware updates, so you may want to wait for a review first.